This invention relates to a method and system for radio communication between at least one parent communication unit and a plurality of slave communication units.
Such a radio communication system includes a cordless telephone system for providing radio communication of a handset with a telephone network. In order to permit a plurality of handsets to come into contact with each telephone line, it is desirable that the cordless telephone system be of the multi-channel access type where one of the handsets shares a plurality of communication channels with the other handsets. With the multi-channel access type cordless telephone system, one handset can communicate through a searched available channel with the telephone line or another handset. A frequency band is used in communication from the former to the latter and another frequency band is used in communication from the latter to the former.
One problem which occurs with this type of radio communication system is that when two or more handsets make answers, in a short interval, to an incoming call transmitted through a telephone line, none of the handsets can communicate with the telephone line due to radio interference between answer signals transmitted from the handsets. Thus, the need exists for a practical approach which permits communication of the telephone line with one handset which makes an answer to the incoming call at a time earlier than the other handsets like wire telephone systems.